A passive optical network (PON) is one system for providing network access over “the last mile.” A PON is a point-to-multipoint network comprised of an optical line terminal (OLT) at a central office (CO), a plurality of optical network units (ONUs) at the user premises, and an optical distribution network (ODN) connecting the OLT and the ONUs. PONs may also comprise remote nodes (RNs) located between the OLTs and the ONUs, for example, at the end of a road where multiple users reside. In recent years, time division multiplexing (TDM) PONs and wavelength division multiplexing (WDM) PONs have been deployed in order to increase bandwidth. In TDM PONs, each ONU may send and receive data across every available wavelength, but only at dedicated time intervals. In WDM PONs, each ONU may send and receive data in a continuous manner, but only at dedicated wavelengths. A hybrid PON combining TDM with WDM can support higher capacity so that an increased number of users can be served by a single OLT with sufficient bandwidth per user. In such a time and wavelength division multiplexed (TWDM) PON, a WDM PON may be overlaid on top of a TDM PON. In other words, multiple wavelengths may be multiplexed together to share a single feeder fiber, and each wavelength may be shared by multiple users using TDM. TWDM PONs, however, present design and cost issues that must be addressed.